Caterpillarchallenger
Caterpillar MTC735
Maintenance schedule, common problems & OEM parts breakdown
The Caterpillar MTC735 is Caterpillar's parts-catalog designation for the Challenger MT735, a rubber-track (Mobil-trac) row-crop and production tractor built from 2002 to 2004 in Jackson, Minnesota (serial prefix AKN). It runs a Caterpillar C-9, an 8.8 L turbocharged six-cylinder diesel with HEUI fuel injection, rated near 235 gross hp (175 kW): about 215.7 hp (160.8 kW) PTO-tested and 160.4 hp (119.6 kW) drawbar-tested. Standard transmission is a 16-speed forward/4-speed reverse powershift, with a 30F/8R creeper option for tillage work. Operating weight runs roughly 28,185-33,000 lb (12,784-14,969 kg) depending on axle spacing, ballast, and fuel load, and axle-bar length lets track gauge adjust from 60 to 160 in to match row spacing. It sits at the entry-power end of Caterpillar's original MT700-series Challenger line, alongside the larger MT745, MT755, and MT765.
Caterpillar sold the design, assembly, and marketing of the new MT-series Challenger tractors to AGCO in March 2002, while continuing to supply the C-9 engine for a period afterward, so early MT735 production straddles the Caterpillar-to-AGCO handoff. AGCO carried the model through 2004 and rolled the wider MT700 line into later B, C, D, and E-series updates with different engines and transmissions; the entry-level 235 hp tier doesn't appear as a distinct model in most spec references past the original series, so treat the MT735 as a closed production run rather than an ongoing model line. In the used and parts market, that makes it a self-contained platform: a Caterpillar-built C-9 core, Cat MTO/DEO/ELC fluids that are easy to source, and a Mobil-trac undercarriage whose wear parts (tracks, mid-rollers, idlers) are still actively supplied across the wider MT700/MT800 family.
Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.
Caterpillar MTC735 specifications
Engine
| Engine model | Caterpillar C-9, inline 6-cylinder turbocharged diesel |
| Displacement | 8.8 L (536 cu in) |
| Gross power (rated) | 175 kW (235 hp) |
| PTO power (tested) | 161 kW (215.7 hp) |
| Emissions tier | Not published on available spec sheets for this build. Production ran 2002-2004, ahead of Tier 3/Tier 4 nonroad diesel requirements for this power class. |
Weights
| Operating weight (base) | approx. 12,784 kg (28,185 lb) |
| Operating weight (ballasted/wide-track configuration) | up to approx. 15,000 kg (33,000 lb) on some listings, varying by axle-bar width and added suitcase/wheel ballast |
| Shipping weight | Not published separately from operating weight on available spec sheets |
| Ground pressure | Not published on available spec sheets |
Dimensions
| Wheelbase | 243 cm (96 in) |
| Track gauge (adjustable, rear axle-bar options) | 152-406 cm (60-160 in) overall adjustment range, built from three axle-bar lengths: 224 cm (88 in), 305 cm (120 in), and 406 cm (160 in) center bars |
| Transport length / width / height | Not consistently published across available spec sheets for this model |
| Ground clearance | Not published on available spec sheets |
Performance
| Drawbar power (tested) | 119.6 kW (160.4 hp) |
| Transmission | Full powershift, 16 forward / 4 reverse; 30 forward / 8 reverse with creeper option |
| Travel speed | Not consistently published for this powershift-equipped generation on available spec sheets; confirm with dealer or operator's manual |
| PTO | 1000 rpm, independent, rear-mounted |
| 3-point hitch | Category III; rated lift capacity up to 7,257 kg (16,000 lb) |
| Steering | Electro-hydraulic, differential-steer track control |
| Gradeability | Not published on available spec sheets |
Service capacities (summary)
| Fuel tank | 447-787 L (118-208 US gal) depending on track-gauge/tank option; some listings cite roughly 345 L (91 US gal) for an alternate configuration, so treat capacity as varying by configuration |
| Hydraulic system flow/pressure | 164.6 L/min (43.5 gpm) at 200 bar (2,900 psi); reservoir volume not published |
| Engine oil capacity | Not published on available spec sheets |
| Cooling system capacity | Not published on available spec sheets |
Values vary by configuration, region, and serial range — confirm against your machine before planning transport or lifts.
MTC735 fluids & capacities
| System | Capacity | Recommended fluid |
|---|---|---|
| Engine crankcase, with oil filter (Cat C9 8.8 L turbocharged 6-cyl diesel, shared block across the MT735-MT765 line) | Not published in the sources reviewed for this specific serial range. Confirm the exact fill quantity on the OMM refill capacities chart before servicing. | Cat DEO diesel engine oil: SAE 10W-30 for ambient -18C to 40C, or SAE 15W-40 for -9.5C to 50C; meets Cat ECF-2 and API CI-4/CH-4/SL. Cat DEO Cold Weather 0W-40 covers -40C to 40C for severe cold. Drain intervals to 500 hours are supported with oil sampling and Cat filters. |
| Cooling system | Not published in the sources reviewed for this model. Confirm on the OMM refill capacities chart. | Cat ELC (Extended Life Coolant), a pre-mixed 50/50 ethylene-glycol formulation giving extended service life versus conventional coolant. Conventional Cat coolant plus a supplemental coolant additive is an acceptable alternate; do not mix coolant types. |
| Fuel tank | Varies by track-gauge and tank option: roughly 447 L (118 US gal) with the narrow 88 in gauge, about 674 L (178 US gal) with the 120 in or 160 in wide gauge, and an optional high-capacity tank near 787 L (208 US gal). One aftermarket tank listing instead cites about 345 L (91 US gal); treat the exact figure as configuration-dependent and confirm against the tank fitted to the machine. | Ultra-low-sulfur No. 2-D diesel fuel per Cat's standard diesel fuel specification. Switch to a winter-blend or No. 1-D in cold climates to prevent fuel gelling and filter plugging. |
| Transmission - 16-speed full powershift (30-speed with creeper option) | Not published in the sources reviewed for this model. Confirm on the OMM refill capacities chart. | Cat MTO (Multipurpose Tractor Oil), Caterpillar's named fluid recommendation for Cat Challenger Tractor drivetrain compartments. Meets API GL-4 and cross-references to Ford New Holland FNHA-2-C-201.00, Massey Ferguson M1135/M1141, John Deere J20C, and Agco Powerfluid 821 XL specifications. |
| Final drives, each side (track drive/sprocket units) | Not published in the sources reviewed for this model. Some Challenger track platforms share fluid with the transmission compartment while others use a separate final-drive fill point; confirm which applies to the serial range and check the OMM refill chart for quantity. | Cat MTO, consistent with the transmission/axle fluid used elsewhere on this platform. Follow the OMM instead if it calls out a distinct final-drive spec for the serial range. |
| Hydraulic system and reservoir | Reservoir volume not published in the sources reviewed. Working hydraulics run at roughly 200 bar (2900 psi) system pressure with flow near 165 L/min (43.5 US gpm) on the 4-6 valve configurations; these are pressure/flow figures, not tank volume. Confirm reservoir capacity on the OMM chart. | Cat MTO, the same fluid used in the transmission compartment on this platform; a shared reservoir arrangement is typical for Challenger track tractors of this generation. Cat notes MTO also suits most Cat hydraulic systems. |
| Axles / differentials | Not applicable. | This is a rubber-belted (Mobil-Trac) track tractor with no front or rear axle differential set. Drive torque passes through the transmission to the track final drives at each side (see final drives row). |
| Grease, all points (spec only) | Not applicable; serviced by grease gun at each fitting per the lubrication interval chart, not a fill volume. | Cat Prime Application Grease, NLGI 2, more than 3% molybdenum disulfide; Caterpillar's named grease recommendation for Cat Challenger Tractors, suited to medium-load, medium-speed, moderate-temperature service in low-moisture conditions. Use a wider-range low-temperature grease for sustained sub-zero operation. |
Capacities are refill values from factory literature — always fill to the dipstick/sight gauge, not the number.
Caterpillar MTC735 maintenance schedule
| Service interval | Tasks |
|---|---|
| Every 10 h |
|
| Every 250 h |
|
| Every 500 h |
|
| Every 1,000 h |
|
| Every 2,000 h |
|
| Every 4,000 h |
|
Servicing the MTC735 beyond the schedule
Predictive Maintenance & Fluid Analysis
Run oil sampling on the C-9's Cat DEO to catch HEUI injector and turbo wear before failure; treat any metal count spike as an injection-system flag, not just a bearing check. The transmission, wet brakes, hydraulics, and PTO share one Cat MTO reservoir, so a single sample at each 500-hour interval reveals wear across all four systems at once. Track the tension gauge on the monitor screen daily; pressure drift signals mid-roller or idler bearing wear long before it's visible.
Corrective & Common Repairs
Expect Mobil-trac belt edge cracking and cord exposure well before tread wear-out, especially on tractors that sat idle between seasons. HEUI injector and hydraulic actuation pump faults show up as hard starts or rough idle on the C-9; check actuation oil pressure before condemning injectors. Mid-roller and idler wheel bearings wear from mud packing in the tri-bogie suspension; listen for play at the hardbar pivot. Powershift clutch pack slip in the 16F/4R box shows up as delayed shifts under load.
Overhaul & Rebuild Points
At high hours, plan a C-9 inframe overhaul around the turbocharger, HEUI injectors, and actuation pump rather than treating them as separate failures; they wear together. The 16F/4R powershift (30F/8R on creeper-equipped tractors) needs clutch pack and control-valve rebuilds as shift quality degrades. Rebuild the tri-bogie hardbar bushings, coil springs, and shocks as a set; replacing one worn idler alone unbalances the suspension. Budget final drive and travel-motor rebuilds together since both share the same duty cycle.
Seasonal & Environment Servicing
Cold starts on the C-9 need block-heater use and a winter-grade Cat DEO change before first frost; HEUI systems are unforgiving of thickened oil. Rubber Mobil-trac belts stiffen in cold weather; reduce track tension slightly and re-check once the belt warms to avoid overstress at the guide lugs. During harvest and tillage season, clear chaff and dust from the radiator, aftercooler, and mid-roller pivots daily, since packed debris in the tri-bogie suspension accelerates bushing wear. Chock and de-tension tracks for off-season storage to prevent flat-spotting.
MTC735 common service parts
| Part number | Part | Notes | |
|---|---|---|---|
| 1R-0762 | Filter As-Fuel | Fuel system service | Check fitment → |
| 161-1705 | Sensor As-Pressure | Lubrication service | Check fitment → |
| 1R-0716 | Filter As-Engine Oil | Lubrication service | Check fitment → |
Always confirm against your machine's serial number — cross-check any part in Heavy Parts AI before ordering.
MTC735 fault codes & troubleshooting
| Code | Meaning | Likely cause | What to do |
|---|---|---|---|
| CID 100-3 (also seen as 100-4) | Engine oil pressure sensor signal voltage is out of the valid range (above normal on -3, below normal on -4). | Corroded or loose sensor connector, chafed harness wire shorted to power or ground, or a failed oil pressure sensor. | Inspect the sensor connector and wiring for corrosion or damage and check supply voltage at the sensor before replacing it. |
| CID 110-3 (also seen as 110-4) | Engine coolant temperature sensor signal voltage is out of the valid range. | Damaged or corroded sensor connector, open circuit in the harness, or a failed coolant temperature sensor. | Check connector pins and harness continuity, then test sensor resistance against spec before replacing the sensor. |
| CID 190-8 | Primary engine speed/timing sensor is sending an abnormal frequency, pulse width, or signal pattern to the ECM. | Incorrect air gap between the sensor and the timing ring, a damaged ring tooth, or a corroded sensor connector. | Check the sensor air gap with a feeler gauge and inspect the timing ring before replacing the sensor. |
| CID 168-4 | Electrical system (battery/charging) voltage seen by the ECM is below the normal operating range. | Weak or discharged batteries, a failing alternator, or corroded battery cables and ground straps. | Load-test the batteries and check charging system output and ground connections. |
| CID 172-3 | Intake manifold (turbo boost) air temperature sensor signal voltage is out of the valid range. | Corroded connector, damaged wiring, or a failed sensor. | Inspect sensor wiring and connector and verify sensor resistance at a known temperature before replacing it. |
| CID 94-17 | Fuel supply pressure to the injection system is below the minimum threshold (least severe level). | Plugged fuel filter, restricted fuel line, or a weak fuel transfer pump. | Replace fuel filters and check fuel supply pressure at the filter base with a gauge. |
| CID 164-3 (also seen as 164-4) | Injection actuation pressure (IAP) sensor signal voltage is out of the valid range; this sensor monitors the hydraulic oil pressure that fires the HEUI injectors. | Connector corrosion or a failing IAP sensor; if actual pressure is abnormal, a worn actuation pump or a leaking injector can trigger the same code. | Check sensor wiring and connector first, then confirm actual actuation pressure with diagnostic software before replacing pump or injector components. |
| Event E361 | Engine coolant temperature has crossed the warning threshold on the machine monitor; higher severity levels of the same event trigger a derate or shutdown. | Low coolant level, a blocked radiator or debris screen, a stuck thermostat, or a slipping or damaged fan drive. | Shut down safely, check coolant level and radiator core for debris, and inspect the thermostat and fan drive. |
Codes and remedies are general guidance for this model family — always confirm with diagnostic tooling and your dealer before major repairs.
MTC735 attachments & work tools
Rear 3-point hitch / quick coupler
Factory rear linkage is a Category III design (some literature for this class lists III/IIIN compatibility), electronically controlled with an integrated quick-coupler as standard fitment. Tested lift capacity on a base-spec unit ran around 7,260 kg (16,000 lb); treat this as class-typical rather than fixed across every build.
Rear PTO
Independent, live rear PTO running at 1000 rpm with a 1-3/4 in (21-spline) output shaft; no 540 rpm option is documented for this class. Drives towed implements such as tillage tools, planters, and sprayers matched to the tractor's horsepower.
Drawbar
Swinging (wide-swing) drawbar is standard for pulling grain carts, tillage equipment, and other towed loads. Tested drawbar output has been reported in the 160-178 hp range depending on claimed vs. tested basis; actual figures vary by configuration/series.
Remote hydraulic valves
Auxiliary remote valve packages of roughly 4 to 6 circuits are offered depending on configuration, fed by a two-pump load-sensing hydraulic system with electronic power-beyond capability for trailed implements carrying their own remote valves. Reported system pressure runs near 200 bar (2900 psi) with flow up to about 165 L/min (43.5 gpm) on tested units.
Track/undercarriage belt width options
Rubber-belt undercarriage is offered in a spread of belt widths across this tractor class, roughly 406-762 mm (16-30 in), with narrower belts suited to row-crop work and wider, higher-flotation belts suited to grain-cart hauling or heavy tillage. Variable gauge spacing lets track centers widen for row-crop clearance; exact width/gauge offerings vary by series and belt supplier.
Undercarriage guarding and maintenance
Debris shields on the roller/track frame limit trash and residue buildup in field conditions. The sealed track undercarriage on this class is described as not requiring routine greasing, reducing service attachments needed versus a steel-track machine.
Ballast weights
Idler-frame ballast weights can be bolted to the front of each track frame to rebalance the tractor when running heavy mounted or trailed implements. Total add-on ballast capacity across both sides has been documented at roughly 1,350 kg (about 3,000 lb) for this class.
Implement classes supported
The rear PTO/hitch/drawbar combination is sized for large tillage tools, planters/seeders, sprayers, and grain carts typical of a high-horsepower row-crop/track-tractor class. No front hitch or front PTO is documented for this model; all implement mounting is rear-only.
All MTC735 assemblies by section
Every catalogued assembly group for the Caterpillar MTC735. Open an assembly to preview the parts inside — full OEM part numbers are available in Heavy Parts AI.
Air Inlet And Exhaust System
174-1590 Elbow Gp-Air Inlet
| 17***90 | Elbow Group-Air Inlet | 1 |
| 1U***46 | Sealant (For Locations A) | 0 |
| 20***60 | Elbow-Air Inlet | 1 |
173-6107 Elbow Gp-Air Inlet
| 13***53 | Stud; (M8x1.25x82.75-mm)(M8x1.25x82.75-mm) | 8 |
| 17***07 | Elbow Group-Air Inlet | 1 |
| 18***71 | Elbow-Air Inlet | 1 |
165-4444 Manifold Gp-Exhaust
| 11***15 | Stud-Taperlock; (M10x85-mm Oal) | 12 |
| 16***98 | Manifold-Exhaust | 1 |
| 16***11 | Gasket | 6 |
171-4687 Manifold Gp-Exhaust
| 11***15 | Stud-Taperlock; (M10x85-mm Oal) | 12 |
| 16***98 | Manifold-Exhaust | 2 |
| 16***11 | Gasket | 6 |
206-4013 Turbocharger Gp
| 1P***51 | Gasket; (Turbocharger) | 1 |
| 20***47 | Turbocharger Group | 1 |
| 20***13 | Turbocharger Group | 1 |
169-3121 Turbocharger Gp
| 16***21 | Turbocharger Group | 1 |
| 19***46 | Turbocharger Group | 1 |
| 1P***51 | Gasket; (Turbocharger) | 1 |
191-5518 Turbocharger Gp
| 19***94 | Turbocharger Group | 1 |
| 19***18 | Turbocharger Group | 1 |
| 1P***51 | Gasket; (Turbocharger) | 1 |
206-2947 Turbocharger Gp
| 13***02 | Clamp As; (Turbine)(Turbine) | 1 |
| 16***63 | Clamp | 2 |
| 17***20 | Hose; (Wastegate) | 1 |
193-3346 Turbocharger Gp
| 13***02 | Clamp As; (Turbine)(Turbine) | 1 |
| 16***63 | Clamp | 2 |
| 17***91 | Hose; (Wastegate) | 1 |
191-5094 Turbocharger Gp
| 13***01 | Housing-Turbine | 1 |
| 13***02 | Clamp As; (Turbine)(Turbine) | 1 |
| 19***94 | Turbocharger Group | 1 |
Basic Engine
164-6100 Camshaft Gp
| 10***94 | Plate-Thrust | 1 |
| 16***00 | Camshaft Group | 1 |
| 1B***05 | Key; (Woodruff) | 1 |
189-6308 Cover Gp-Cylinder Block
| 18***08 | Cover Group-Cylinder Block | 1 |
| 5F***81 | Gasket To Flywheel Housing Drain Tube Assembly | 1 |
| 5F***59 | Flange | 1 |
183-3649 Cover Gp-Cylinder Block
| 18***49 | Cover Group-Cylinder Block; -Rear | 1 |
| 20***87 | Breather As; (Crankcase) | 1 |
| 21***10 | Gasket | 1 |
118-1727 Cover Gp-Front Housing
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 13***19 | Seal-Integral; (Integral) | 1 |
| 4W***26 | Cover | 1 |
166-1775 Cover Gp-Front Housing
| 06***55 | Seal-O-Ring (Id=47.22mm) | 1 |
| 12***57 | Washer; (10.85x19.3x1.27-mm Thk) | 2 |
| 13***22 | Stud | 2 |
216-3047 Cover Gp-Front Housing
| 06***55 | Seal-O-Ring (Id=47.22mm) | 1 |
| 06***97 | Cap-Oil Filler; (Engine Oil) | 1 |
| 12***57 | Washer; (10.85x19.3x1.27-mm Thk) | 2 |
164-6490 Cover Gp-Valve Mechanism
| 16***90 | Cover Group-Valve Mechanism | 1 |
| 20***39 | Fastener Assem. | 9 |
| 21***01 | Seal-Bulk; (23-Dm)(Valve Mechanism Cover) | 0 |
164-6148 Crankshaft Gp
| 15***39 | Bearing-Main; (Standard) | 7 |
| 16***47 | Crankshaft Assem. | 1 |
| 16***66 | Plate-Thrust | 2 |
204-9538 Cylinder Block As
| 0L***26 | Plug -13mm(.512 In.) Outside Dia. | 2 |
| 17***54 | Bolt-Hex Head; (M16x160mm) | 14 |
| 20***05 | Bearing-Sleeve; (Camshaft) | 2 |
221-3248 Cylinder Block As
| 0L***26 | Plug -13mm(.512 In.) Outside Dia. | 2 |
| 17***54 | Bolt-Hex Head; (M16x160mm) | 14 |
| 20***05 | Bearing-Sleeve; (Camshaft) | 2 |
161-3406 Cylinder Block Gp
| 0S***19 | Plug-Cup | 1 |
| 16***06 | Cylinder Block Group | 1 |
| 1W***07 | Sleeve | 2 |
204-9539 Cylinder Block Gp
| 03***53 | Seal-O-Ring; (08.92mm Id) | 1 |
| 16***24 | Seal-Liner | 6 |
| 19***62 | Liner-Cylinder Block | 6 |
220-1952 Cylinder Block Gp
| 03***53 | Seal-O-Ring; (08.92mm Id) | 1 |
| 16***24 | Seal-Liner | 6 |
| 19***62 | Liner-Cylinder Block | 6 |
201-2180 Cylinder Head As
| 17***88 | Seat-Valve | 12 |
| 17***90 | Seat-Valve | 12 |
| 17***37 | Sleeve-Injector | 6 |
210-5985 Cylinder Head As
| 17***88 | Seat-Valve | 12 |
| 17***90 | Seat-Valve | 12 |
| 21***85 | Cylinder Head As | 1 |
161-3405 Cylinder Head Gp
| 16***05 | Cylinder Head Group | 1 |
| 16***71 | Fastener Group-Cylinder Head | 26 |
| 18***15 | Gasket Assem. | 1 |
210-5984 Cylinder Head Gp
| 15***06 | Seal-O-Ring; (11.89mm Id) | 5 |
| 16***42 | Valve; (Intake) | 12 |
| 16***44 | Guide-Valve | 24 |
201-2181 Cylinder Head Gp
| 03***53 | Seal-O-Ring; (08.92mm Id) | 6 |
| 15***06 | Seal-O-Ring; (11.89mm Id) | 5 |
| 16***42 | Valve; (Intake) | 12 |
210-5987 Cylinder Head Gp
| 16***71 | Fastener Group-Cylinder Head | 26 |
| 18***15 | Gasket Assem. | 1 |
| 21***84 | Cylinder Head Group | 1 |
169-3539 Damper & Pulley Gp
| 15***36 | Pulley-Crankshaft; (8-Groove) | 1 |
| 16***39 | Damper & Pulley Group | 1 |
| 20***19 | Damper As | 1 |
192-3833 Damper & Pulley Gp
| 15***36 | Pulley-Crankshaft; (8-Groove) | 1 |
| 16***21 | Damper Assem. | 1 |
| 19***33 | Damper & Pulley Group | 1 |
202-0103 Drain Gp-Engine Oil
| 20***03 | Drain Group-Engine Oil | 1 |
| 3K***60 | Seal Pilot Manifold On; Seal To Boom Check Valve Drain | 1 |
| 6V***38 | Valve-Shutoff; (Engine Oil Pan Drain) | 1 |
202-2025 Drive Gp-Fan
| 10***26 | Retainer-Bearing | 1 |
| 11***38 | Plate; (Thrust) | 1 |
| 12***56 | Shaft-Fan | 1 |
167-0171 Fastener Gp-Cylinder Head
| 16***71 | Fastener Group-Cylinder Head | 1 |
| 18***63 | Bolt; (M16x2x180-mm) | 1 |
| 9X***68 | Washer; (17.5x30x3.5-mm Thk) | 1 |
169-3106 Fastener Gp-Engine
| 16***06 | Fastener Group-Engine | 1 |
| 4K***90 | Washer; (8.6x17.3x1.6-mm Thk) | 6 |
| 6V***19 | Bolt; (M8x1.25x40-mm) | 6 |
117-2794 Fastener Gp-Flywheel
| 11***94 | Fastener Group-Flywheel; (Flywheel) | 1 |
| 5P***47 | Washer (Bracket To Valve Support) | 8 |
| 9X***21 | Bolt; (Locking) (M16x2.0x45mm) | 8 |
166-1788 Fastener Gp-Front Housing
| 16***88 | Fastener Group-Front Housing | 1 |
| 6V***17 | Bolt; (M8x1.25x30-mm)(Location Z) | 5 |
| 8T***00 | Bolt (M8x1.25x60mm); (M8x1.25x60-mm) | 1 |
173-7123 Fastener Gp-Front Housing
| 17***23 | Fastener Group-Front Housing | 1 |
| 6V***17 | Bolt; (M8x1.25x30-mm)(Location Z) | 4 |
| 8T***00 | Bolt (M8x1.25x60mm); (M8x1.25x60-mm) | 1 |
116-4556 Fastener Gp-Front Housing
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 5P***45 | Washer-Hard; (13.5x25.5x3-mm Thk)(Turbocharger Blanking Plate) | 6 |
| 6V***36 | Bolt; (M12x1.75x70-mm) | 6 |
171-4684 Flywheel Gp
| 15***05 | Pulley-Rear | 1 |
| 16***56 | Flywheel As | 1 |
| 16***87 | Gear-Flywheel; (134-Teeth)(Id 405.14mm) | 1 |
145-9112 Flywheel Gp
| 14***53 | Flywheel As | 1 |
| 14***12 | Flywheel Group | 1 |
| 4N***14 | Gear; (113-Teeth)(Flywheel Starter) | 1 |
201-5534 Flywheel Gp
| 15***05 | Pulley-Rear | 1 |
| 16***87 | Gear-Flywheel; (134-Teeth)(Id 405.14mm) | 1 |
| 17***86 | Bolt; (M16x2x115-mm) | 8 |
155-7918 Gear Gp-Front
| 11***69 | Plate-Thrust | 1 |
| 11***72 | Bearing | 1 |
| 11***19 | Plate-Retaining | 1 |
155-7935 Housing Gp-Flywheel
| 06***55 | Seal-O-Ring (Id=47.22mm) | 1 |
| 15***35 | Housing Group-Flywheel | 1 |
| 1P***69 | Plug-Seal; (Flywheel Housing Drain) | 3 |
165-4446 Housing Gp-Front
| 16***46 | Housing Group-Front | 1 |
| 1U***46 | Sealant (For Locations A) | 0 |
| 23***16 | Housing-Front | 1 |
193-3293 Lifting Gp-Engine
| 19***93 | Lifting Group-Engine | 1 |
| 19***94 | Plate-Lift Eye | 1 |
| 5P***45 | Washer-Hard; (13.5x25.5x3-mm Thk)(Turbocharger Blanking Plate) | 3 |
169-3113 Lifting Gp-Engine
| 16***85 | Plate-Lifting; (Rear) | 1 |
| 16***13 | Lifting Group-Engine | 1 |
| 5P***45 | Washer-Hard; (13.5x25.5x3-mm Thk)(Turbocharger Blanking Plate) | 3 |
187-3884 Mounting Gp-Fan Drive
| 18***84 | Mounting Group-Fan Drive | 1 |
| 18***87 | Support As-Fan | 1 |
| 18***56 | Block | 1 |
187-3076 Pan Gp-Oil
| 18***85 | Pan-Oil; (Engine Oil) | 1 |
| 18***76 | Pan Group-Oil; -Engine | 1 |
| 19***14 | Gasket-Oil Pan; (Engine) | 1 |
188-9141 Piston & Rod Gp
| 15***51 | Skirt-Piston | 1 |
| 16***72 | Bearing-Connecting Rod | 1 |
| 16***97 | Bolt | 2 |
177-7878 Piston Gp
| 17***78 | Piston Group | 1 |
| 18***41 | Piston & Rod Group | 6 |
206-6437 Plug Gp-Engine
| 20***37 | Plug Group-Engine | 1 |
| 3D***24 | O-Ring - For Oil Drain & Level Plug (Items 3 & 7) | 2 |
| 5P***17 | Adapter- To Logic Valve 1u***59 | 1 |
169-3105 Plug Gp-Engine
| 16***05 | Plug Group-Engine | 1 |
| 3D***24 | O-Ring - For Oil Drain & Level Plug (Items 3 & 7) | 1 |
| 6V***49 | Seal-O-Ring (Id=11.89mm); (11.89-mm Id) | 2 |
7e-2313 Drain Gp-Engine Oil
| 3K***60 | Seal Pilot Manifold On; Seal To Boom Check Valve Drain | 1 |
| 7E***13 | Plug Group-Oil Pan | 1 |
| 9X***30 | Plug-Drain; (Magnetic)(Engine Oil Pan) | 1 |
193-1726 Pulley Gp
| 10***26 | Retainer-Bearing | 1 |
| 11***38 | Plate; (Thrust) | 1 |
| 12***56 | Shaft-Fan | 1 |
175-3223 Pulley As-Idler
| 12***90 | Bolt; (M10x1.5) | 1 |
| 12***91 | Cover-Dust | 1 |
| 12***92 | Pulley As-Idler; (8-Groove) | 1 |
213-9321 Rocker Arm Gp -Intake
| 16***49 | Rocker Arm As | 1 |
| 18***65 | Screw-Adjustment; (M10x1.5-Thd) | 1 |
| 21***21 | Rocker Arm Group; -Intake | 1 |
213-9320 Rocker Arm Gp -Exhaust
| 16***47 | Rocker Arm As | 1 |
| 18***65 | Screw-Adjustment; (M10x1.5-Thd) | 1 |
| 21***20 | Rocker Arm Group; -Exhaust | 1 |
178-3899 Seal Gp-Crankshaft
| 11***21 | Seal Group-Crankshaft; (Front) | 1 |
| 17***99 | Seal Group-Crankshaft | 1 |
| 18***61 | Seal Group-Crankshaft; (Rear) | 1 |
185-5334 Support Gp-Engine
| 18***34 | Support Group-Engine; -Front | 1 |
| 20***44 | Support-Engine | 2 |
| 6V***44 | Bolt; (M16x2.0x35mm) | 4 |
171-4685 Support Gp-Engine
| 16***06 | Support-Rear | 1 |
| 17***85 | Support Group-Engine | 1 |
| 1U***46 | Sealant (For Locations A) | 0 |
155-7927 Valve Mechanism Gp
| 13***79 | Rod-Valve Push; (Valve Push) | 12 |
| 15***27 | Valve Mechanism Group | 1 |
| 16***37 | Lifter As-Valve | 12 |
215-9571 Valve Mechanism Gp
| 16***45 | Shaft As-Rocker Arm | 1 |
| 16***59 | Spring | 6 |
| 16***69 | Stand; (End) | 2 |
163-2450 Valve Mechanism Gp
| 16***94 | Insert-Rocker Arm | 2 |
| 16***45 | Shaft As-Rocker Arm | 1 |
| 16***46 | Rocker Arm Group; (Exhaust) | 6 |
Cooling System
188-3826 Cooler Gp-Engine Oil
| 18***26 | Cooler Group-Engine Oil | 1 |
| 20***93 | Gasket | 1 |
| 23***56 | Core As-Oil Cooler; (Engine) | 1 |
187-3066 Cover Gp-Water Outlet
| 18***07 | Seal-Integral | 1 |
| 18***36 | Cover | 1 |
| 18***66 | Cover Group-Water Outlet | 1 |
165-4461 Lines Gp-Water
| 14***11 | Plug Group | 2 |
| 16***61 | Lines Group-Water; -Water Temperature Regulator | 1 |
| 16***24 | Hose | 1 |
208-0440 Lines Gp-Water
| 16***24 | Hose | 1 |
| 19***57 | Gasket; (Water Regulator Housing)(Temperature) | 1 |
| 20***40 | Lines Group-Water; -Water Temperature Regulator | 1 |
205-4013 Plug Gp-Water Lines
| 20***13 | Plug Group-Water Lines; -Coolant | 1 |
| 20***34 | Plug-Cup; (73.38-mm Dia) | 2 |
| 7L***56 | Plug-Cup; (67.03-mm Dia) | 2 |
187-8982 Pump Gp-Water
| 06***69 | Stem | 1 |
| 14***88 | Seal As; (Water Pump) | 1 |
| 17***44 | Cover | 1 |
208-0332 Pump Gp-Water
| 14***88 | Seal As; (Water Pump) | 1 |
| 17***44 | Cover | 1 |
| 17***52 | Shaft As | 1 |
208-0333 Pump Gp-Water
| 20***32 | Pump Group-Water | 1 |
| 20***33 | Pump Group-Water | 1 |
| 2M***53 | Seal--To Seal Brake Housing To Main Housing | 1 |
165-4478 Pump Gp-Water
| 16***78 | Pump Group-Water | 1 |
| 18***82 | Pump Group-Water | 1 |
| 2M***53 | Seal--To Seal Brake Housing To Main Housing | 1 |
Electrical And Starting System
188-3506 Alternator Gp-Charging
| 11***79 | Alternator Group-Charging | 1 |
| 12***40 | Support-Alternator | 1 |
| 13***82 | Support-Alternator | 1 |
117-1379 Alternator Gp-Charging
| 03***12 | Screw-Forming; (10-24x0.5-In) | 3 |
| 10***86 | Stator As-Alternator | 1 |
| 11***79 | Alternator Group-Charging | 1 |
180-6004 Connection Gp-Electrical
| 10***29 | Stud; (M10x1.5-Thd) | 1 |
| 10***03 | Cap; (Stud Protector) | 1 |
| 18***04 | Connection Group-Electrical | 1 |
206-6446 Connection Gp-Electrical
| 20***46 | Connection Group-Electrical; -Air Inlet Heater | 1 |
| 20***96 | Cable As | 1 |
| 3T***88 | Terminal-Ring; (4-Ga, 7/16-In Screw) | 1 |
208-2385 Connection Gp-Electrical
| 10***29 | Stud; (M10x1.5-Thd) | 1 |
| 10***03 | Cap; (Stud Protector) | 1 |
| 20***85 | Connection Group-Electrical | 1 |
165-4468 Control & Mtg Gp-Engine Elek
| 10***28 | Spacer-Special; (12.7x26x28.7-mm Thk) | 2 |
| 16***68 | Control & Mtg Group-Engine Elek | 1 |
| 16***11 | Spacer | 2 |
196-4172 Control Gp-Engine Electronic
| 18***72 | Screw-Pan Head; (No 8-32x9.52-mm)(Wax Coated) | 1 |
| 19***72 | Control Group-Engine Electronic | 1 |
| 7X***15 | Strap; (Grounding) | 1 |
196-4173 Control Gp-Engine Electronic
| 19***72 | Control Group-Engine Electronic | 1 |
| 19***73 | Control Group-Engine Electronic | 1 |
201-0194 Heater Gp-Air Inlet
| 19***59 | Heater As-Air Inlet | 1 |
| 1U***46 | Sealant (For Locations A) | 0 |
| 20***94 | Heater Group-Air Inlet | 1 |
205-6289 Heater Gp-Jacket Water
| 18***36 | Cord As; -Jacket Water Heater | 1 |
| 20***89 | Heater Group-Jacket Water | 1 |
| 20***34 | Plug-Cup; (73.38-mm Dia) | 2 |
4p-1479 Heater Gp-Starting Aid
| 15***11 | Heater As; (Starting Aid) | 1 |
| 1U***46 | Sealant (For Locations A) | 0 |
| 4P***79 | Heater Group-Starting Aid; -Air Inlet Heater | 1 |
177-9816 Mounting Gp-Solenoid
| 17***16 | Mounting Group-Solenoid; -Starting Aid | 1 |
| 19***85 | Bracket | 1 |
| 3E***53 | Washer-Hard; (11x25x3-mm Thk) | 2 |
165-4469 Sensor Gp-Engine
| 11***85 | Seal-O-Ring; (13.94mm Id) | 2 |
| 13***11 | Sensor Group-Temperature; (Transmission Lubrication Oil) | 2 |
| 13***67 | Seal-O-Ring | 1 |
169-3300 Sensor Gp-Speed -Timing
| 16***00 | Sensor Group-Speed; -Engine Timing | 1 |
191-6587 Sensor Gp-Temperature -Engine Oil
| 15***43 | Sleeve; (2.8-Dm) | 0 |
| 15***61 | Wedge-Plug Lock; (2-Pin) | 1 |
| 15***70 | Kit-Connecting Plug; (2-Pin)(Engine Sensor Wiring Harness) | 1 |
130-9811 Sensor Gp-Temperature
| 13***11 | Sensor Group-Temperature; (Transmission Lubrication Oil) | 1 |
207-1524 Starting Motor Gp-Electric
| 03***23 | Bolt; (1/4-28x1-In) | 5 |
| 20***89 | Kit-Solenoid; (12-Volt)(Starting Motor) | 1 |
| 20***24 | Starting Motor Group-Electric | 1 |
101-8936 Starting Motor Gp-Electric
| 10***36 | Starting Motor Group-Electric | 1 |
| 15***25 | Gasket | 1 |
| 20***24 | Starting Motor Group-Electric | 1 |
175-2303 Switch Gp-Magnetic -Air Inlet Heater
| 01***80 | Lockwasher | 2 |
| 10***02 | Kit-Receptacle; (2-Pin)(Engine Sensor Wiring Harness) | 1 |
| 17***03 | Switch Group-Magnetic; -Air Inlet Heater | 1 |
209-1953 Wiring Gp-Electronic Control
| 00***35 | Protector | 1 |
| 10***20 | Plug As-Connector; (2-Pin) | 1 |
| 10***02 | Kit-Receptacle; (2-Pin)(Engine Sensor Wiring Harness) | 2 |
188-9869 Wiring Gp-Electronic Control
| 00***35 | Protector | 1 |
| 01***80 | Lockwasher | 2 |
| 10***20 | Plug As-Connector; (2-Pin) | 1 |
Engine Arrangement
177-1414 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
194-4160 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
179-4956 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
179-4958 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
177-1418 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
179-4954 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
177-1416 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
177-1420 Engine Ar
| 10***36 | Starting Motor Group-Electric | 1 |
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***94 | Fastener Group-Flywheel; (Flywheel) | 1 |
179-4952 Engine Ar
| 11***56 | Fastener Group-Front Housing; (Housing) | 1 |
| 11***27 | Cover Group-Front Housing; -Accessory Drive | 1 |
| 16***90 | Cover Group-Valve Mechanism | 1 |
194-4161 Engine Ar-Core
| 15***18 | Gear Group-Front | 1 |
| 15***27 | Valve Mechanism Group | 1 |
| 16***06 | Cylinder Block Group | 1 |
177-1421 Engine Ar-Core
| 15***18 | Gear Group-Front | 1 |
| 15***27 | Valve Mechanism Group | 1 |
| 16***05 | Cylinder Head Group | 1 |
177-1417 Engine Ar-Core
| 15***18 | Gear Group-Front | 1 |
| 15***27 | Valve Mechanism Group | 1 |
| 16***06 | Cylinder Block Group | 1 |
177-1419 Engine Ar-Core
| 15***18 | Gear Group-Front | 1 |
| 15***27 | Valve Mechanism Group | 1 |
| 16***06 | Cylinder Block Group | 1 |
177-1415 Engine Ar-Core
| 15***18 | Gear Group-Front | 1 |
| 15***27 | Valve Mechanism Group | 1 |
| 16***06 | Cylinder Block Group | 1 |
Frame And Body
206-5947 Mounting Gp -Solenoid
| 20***46 | Bracket | 1 |
| 20***47 | Mounting Group; -Solenoid | 1 |
| 3E***53 | Washer-Hard; (11x25x3-mm Thk) | 2 |
Fuel System
236-0962 Injector Gp-Fuel
| 10***07 | Seal-O-Ring; (Fuel System) | 1 |
| 14***03 | Seal-O-Ring; (Fuel System) | 1 |
| 14***40 | Ring-Backup; (37.36mm Od), Flasher Switch; Hazard, Replaces 421164a1, Flasher Switch | 1 |
217-2570 Injector Gp-Fuel
| 10***07 | Seal-O-Ring; (Fuel System) | 1 |
| 14***03 | Seal-O-Ring; (Fuel System) | 1 |
| 14***40 | Ring-Backup; (37.36mm Od), Flasher Switch; Hazard, Replaces 421164a1, Flasher Switch | 1 |
204-7454 Lines Gp-Fuel
| 03***42 | Elbow Hose Assembly To | 1 |
| 03***47 | Elbow-Filtered Fuel From Based Assembly | 3 |
| 03***55 | Tee-Flared | 1 |
189-3803 Lines Gp-Fuel Filter
| 00***15 | Insert | 1 |
| 03***42 | Elbow Hose Assembly To | 1 |
| 03***47 | Elbow-Filtered Fuel From Based Assembly | 1 |
172-5780 Pump Gp-Unit Injection
| 17***80 | Pump Group-Unit Injection | 1 |
| 19***20 | Bolt-Socket Head; (M8x1.25x63-mm) | 2 |
| 21***70 | Injector Group-Fuel | 1 |
166-1759 Pump Gp-Unit Injection
| 16***59 | Pump Group-Unit Injection | 1 |
| 17***80 | Pump Group-Unit Injection | 6 |
204-4944 Pump Gp-Unit Injector Hyd
| 20***44 | Pump Group-Unit Injector Hydraulic | 1 |
165-4450 Pump Gp-Unit Injector Hyd
| 03***50 | Elbow (Check Valve Drain Tube) | 1 |
| 15***06 | Seal-O-Ring; (11.89mm Id) | 3 |
| 15***07 | Seal-O-Ring | 2 |
Lubrication System
183-3700 Filter Gp-Engine Oil
| 03***53 | Seal-O-Ring; (08.92mm Id) | 1 |
| 18***56 | Base As-Oil Filter | 1 |
| 18***00 | Filter Group-Engine Oil | 1 |
206-6441 Filter Gp-Engine Oil
| 1R***16 | Filter As-Engine Oil; (Standard Efficiency) | 1 |
| 20***62 | Seal | 1 |
| 20***41 | Filter Group-Engine Oil | 1 |
187-3077 Fumes Disposal Gp
| 18***77 | Fumes Disposal Group | 1 |
| 19***31 | Bracket | 1 |
| 19***10 | Hose-Fumes Disposal | 1 |
201-5535 Fumes Disposal Gp
| 12***71 | Clamp-Hose | 1 |
| 1D***64 | Spacer; (15.8x21.34x25-mm Thk) | 1 |
| 20***35 | Fumes Disposal Group | 1 |
176-5328 Gauge Gp-Oil Level (Dipstick)
| 17***28 | Gauge Group-Oil Level (Dipstick); -Engine | 1 |
| 18***14 | Gauge-Oil Level; (Dipstick, Engine) | 1 |
| 18***16 | Tube As-Guide; (Rh) | 1 |
187-0710 Gauge Gp-Oil Level (Dipstick)
| 18***10 | Gauge Group-Oil Level (Dipstick); -Engine | 1 |
| 18***16 | Tube As-Guide; (Rh) | 1 |
| 19***33 | Gauge-Oil Level; (Dipstick, Engine) | 1 |
192-2833 Lines Gp-Engine Oil
| 03***34 | Seal-O-Ring | 1 |
| 19***33 | Lines Group-Engine Oil | 1 |
| 19***52 | Gasket | 1 |
188-3028 Lines Gp-Engine Oil
| 16***80 | Tube As | 1 |
| 18***28 | Lines Group-Engine Oil | 1 |
| 19***74 | Elbow-Outlet | 1 |
188-8840 Lines Gp-Turbocharger Oil
| 18***99 | Connector As | 1 |
| 18***40 | Lines Group-Turbocharger Oil | 1 |
| 18***41 | Hose As | 1 |
165-4465 Lines Gp-Turbocharger Oil
| 16***65 | Lines Group-Turbocharger Oil | 1 |
| 16***66 | Tube As | 1 |
| 18***98 | Connector As | 1 |
195-8098 Pump Gp-Engine Oil
| 19***98 | Pump Group-Engine Oil; (Engine Oil) | 1 |
| 21***22 | Pump As-Engine Oil | 1 |
| 21***46 | Gerotor Pump Group | 1 |
Operator Station
188-3507 Compressor Gp-Refrigerant
| 12***37 | Support-Compressor | 1 |
| 18***07 | Compressor Group-Refrigerant | 1 |
| 2Y***29 | Nut-Hard; (M10 X 1.5) | 2 |
MTC735 serial number reference
The PIN/serial plate on this tractor sits on the main frame, front left side, and is often repeated on a ROPS/cab pillar tag. Read the first three characters as the prefix, which fixes the model and build source, and the digits that follow as the sequential unit number within that run. Match the full PIN against a parts or service manual's stated serial break (e.g., a prefix followed by a starting number and "-Up") to confirm which book covers your unit before ordering parts.
| Prefix | Identifies | Notes |
|---|---|---|
| AKN | Challenger 700-series track tractor cataloged by Caterpillar as MTC735, built and sold under the AGCO Challenger nameplate as MT735 | Assembled in the US (Jackson, Minnesota), model years roughly 2002-2004. The AKN run breaks out by build year as AKN20000 (2002), AKN30000 (2003), and AKN40000 (2004), with a later production block starting at AKN40001 still being documented into 2005. Caterpillar sold the Challenger tractor line's design, assembly, and marketing to AGCO in a deal that closed in March 2002 and stayed on as engine and driveline supplier, which is why the Cat-cataloged MTC735 and the AGCO-dataplated MT735 are the same physical machine. Power comes from a Caterpillar six-cylinder diesel of roughly 8.8 L (C9 family), rated near 235 gross hp (175 kW). A later "B" generation (MT735B and siblings) is a separate, newer production run; do not mix its data with this base AKN-prefixed machine. Treat the exact start/end of the AKN run as a starting point and confirm the full PIN break with a dealer before ordering serial-specific parts. |
Frequently asked questions
What engine does the Caterpillar MTC735 use?
A Caterpillar C-9, an 8.8 L turbocharged inline-six diesel with HEUI fuel injection. It's rated near 235 gross hp (175 kW), with PTO-tested output around 215.7 hp (160.8 kW) and drawbar-tested output around 160.4 hp (119.6 kW).
What is the operating weight of the MTC735?
Roughly 28,185 lb (12,784 kg) in a standard configuration, climbing toward 33,000 lb (14,969 kg) with wider axle spacing, added ballast, and a full fuel load. Exact weight varies by configuration.
What replaced the Caterpillar MTC735?
Nothing directly. Caterpillar exited farm-tractor production in 2002, selling the MT-series design, assembly, and marketing to AGCO while still supplying the C-9 engine for a time. AGCO continued the MT735 through 2004 under the Challenger brand and evolved the broader MT700 line through several later series with different engines and transmissions; there's no single one-for-one successor model.
What MTC735 owners discuss
What's the most common C-9 engine complaint from MT735 owners?
Hard starting, rough idle, or a lack of power usually traces back to the HEUI fuel system rather than a straight fuel problem. This engine fires its injectors using high-pressure engine oil, so a weakening high-pressure oil pump, worn injectors, or oil that has run past its change interval will all show up as starting or power complaints. A code pointing at injection actuation pressure means check the oil pump before condemning injectors. Idle oil pressure under roughly 500 psi (34 bar) is a red flag. Because this system is more oil-quality-sensitive than a common-rail engine, staying on the service interval with the correct diesel engine oil grade matters more here than on newer engines. Have your dealer verify HEUI pump versus injector diagnosis before replacing parts.
What wears out first on the rubber-track undercarriage?
Mid-roller (bogie) wheels and the rubber guide lugs bonded to the track belt go first. Original steel-core, rubber-coated mid-rollers tend to have the coating separate from the core over time, which is why poly-coated replacement wheels are the common upgrade. Individual guide lugs on the track crack or shear off well before the belt itself is worn out; bolt-on replacement lugs are the standard fix rather than scrapping the track, and on steep or side-hill ground it is common practice to bolt lugs down preventively before they are lost. Belt life itself depends heavily on driving style: minimizing tight pivot turns on hard or abrasive ground stretches track life noticeably compared to a machine run hard.
Why does a track keep losing tension?
Tension is held by a hydraulic cylinder backed by a nitrogen-charged accumulator, normally charged in the roughly 2700-2900 psi (186-200 bar) range. A track that needs re-tensioning every few days, rather than settling once and holding, points to a leaking cylinder seal or a discharged/failed accumulator, not normal wear. If the tensioning circuit has been opened for any repair, trapped air must be bled through the fill valve until no large bubbles show in the drain hose; skipping that step gives an inconsistent, spongy tension reading afterward. Because the accumulator is a stored-pressure component, have your dealer verify nitrogen charge and seal condition rather than servicing it in the field.
Is the powershift transmission reliable, and what breaks it?
The 16-speed powershift holds up well under normal load-shift driving. The main owner-caused wear pattern is riding the inching pedal like a clutch pedal instead of using it only for brief fine-spotting; sustained partial engagement heats the clutch packs and accelerates wear that a properly used powershift wouldn't see. Occasional unexpected drops to neutral or delayed up/downshifts on this transmission family point to a control valve or calibration issue more often than a mechanical failure. Transmission oil has a set change interval, and the transmission has to be recalibrated with dealer diagnostic software every time that oil is changed; skipping the recalibration is a common reason an otherwise sound transmission starts shifting rough afterward.
How many hours before the final drives or gearbox need major work?
Long-term owners treat final drive gear renewal in the 7,000-8,000 hour range as the first predictable major driveline expense, arriving around the same time the original track belts are due for replacement, not as a sign of abuse. The base machine is built on Caterpillar's construction-equipment platform, which owners credit for a long overall design life, and total cost of ownership over a high-hour machine's life is described as reasonable once that one job is priced in. Watch for metal debris during routine oil and filter checks well before gear noise becomes audible.
What causes odd electrical faults or sensor codes on these machines?
On this generation of Caterpillar/Challenger control-module electronics, faults more often trace to corroded connectors and poor grounds than to a failed control module itself. A machine that starts but won't move, or that throws a fault that clears itself, points to wiring first. Before condemning a control module, swap it into a known-good machine (or swap a known-good one in) to confirm the fault follows the part rather than the harness. Hydraulic-status sensors, including track tension sensing, can set a false fault from a bad connector just as easily as from a real hydraulic problem. Have your dealer verify control module diagnosis before replacing an electronic component.
What should I check before buying a used MTC735?
Cross-check the hour meter against physical wear: a low-hour listing with heavily worn guide lugs or thin mid-roller poly doesn't add up. Cold-start the engine and watch for hard starting or excess white smoke as a first flag for HEUI pump or injector wear, and ask for a recent oil sample if one exists. Run the transmission through its full range and confirm it doesn't hunt for gears or drop to neutral unexpectedly; ask when it was last recalibrated after an oil change. Inspect both tracks for missing guide lugs and exposed cord, and confirm track tension holds overnight rather than bleeding down. Ask about final drive service history on anything approaching 6,000-7,000 hours. Check the rockshaft and remote spool valves for external leaks, a common minor-repair item on higher-hour machines. Have your dealer pull a full fault-code history and, if possible, an oil analysis before finalizing a purchase on any machine with unknown maintenance history.
Compiled from owner and technician discussions across the industry — experiences vary by serial range and machine history.
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